# how to make physics working model to demonstrate simple machines

Creating a physics working model to demonstrate simple machines using cardboard and colored paper can be an engaging and educational project.

Here’s a step-by-step guide to making a rotatable model that showcases a lever, pulley, inclined plane, wheel and axle, and scissors.

### Materials Needed:

1. Cardboard sheets
2. Colored paper
3. Scissors
5. Ruler
6. Markers or pens (for detailing)
7. Brass fasteners (split pins) or small nails (for rotating parts)
8. String (for the pulley)
9. Small dowels or sticks (for axles and supports)
10. Paper clips or small weights (to demonstrate the machines)

### Step by Step Video Instructions:

#### 1. Prepare the Base:

• Cut a large piece of cardboard to serve as the base for your model. This will support all the simple machines.

#### 2. Create a Lever:

• Fulcrum: Cut a small triangular piece of cardboard to serve as the fulcrum.
• Lever Arm: Cut a long rectangular piece of cardboard to serve as the lever arm. Make sure it can pivot on the fulcrum.
• Assembly: Place the lever arm on the fulcrum and attach them to the base using a brass fastener, allowing the lever to pivot.

#### 3. Create a Pulley:

• Pulley Wheel: Cut a circular piece of cardboard to serve as the pulley wheel.
• Pulley Groove: Cut a smaller circle from the center of the pulley wheel to create a groove for the string.
• Support: Cut two strips of cardboard and attach them vertically to the base to hold the pulley wheel.
• Assembly: Attach the pulley wheel between the supports using a small dowel or stick as an axle. Wrap a piece of string around the pulley.

#### 4. Create an Inclined Plane:

• Plane: Cut a rectangular piece of cardboard to serve as the inclined plane.
• Supports: Cut two triangular pieces of cardboard to support the inclined plane at an angle.
• Assembly: Attach the inclined plane to the supports and then to the base.

#### 5. Create a Wheel and Axle:

• Wheels: Cut two identical circular pieces of cardboard to serve as wheels.
• Axle: Use a small dowel or stick as the axle.
• Assembly: Attach the wheels to either end of the axle. Ensure the axle can rotate freely when attached to the base.

#### 6. Create Scissors (a type of lever):

• Blades: Cut two long, narrow pieces of cardboard to serve as the scissor blades.
• Pivot: Attach the blades together at the middle using a brass fastener, allowing them to pivot like real scissors.
• Handles: Cut and attach small loops at the ends of the blades for handles.
• Assembly: Place the scissors on the base and label them.

### Demonstration and Explanation:

1. Lever: Place a small weight (e.g., a paper clip) on one end of the lever and show how pressing on the other end lifts the weight.
2. Pulley: Attach a small weight to the string and show how pulling the string raises the weight.
3. Inclined Plane: Place a small object at the top of the inclined plane and let it roll or slide down to demonstrate how it reduces the effort needed to lift the object.
4. Wheel and Axle: Roll the wheel and axle to show how it reduces friction and makes it easier to move objects.
5. Scissors: Use the cardboard scissors to cut a piece of paper, demonstrating how they work as a lever.